1. Field of the Invention
The present invention relates to a rotary electric shaver which rotatively drives inner cutters, which are in resilient contact with inner bottom surfaces of circular outer cutters.
2. Description of the Related Art
There has been known a so-called rotary electric shaver which has circular or disk-shaped outer cutters and inner cutter rotating on the inner side of the outer cutters so that beard hair entering the hair introduction slits formed in the outer cutters is cut by the rotating inner cutters. As this type of electric shaver, there has been known in which outer cutter installing holes are formed in an outer cutter frame secured to a shaver main body and circular outer cutters are supported in the outer cutter installing holes such that the outer cutters are slightly movable in a vertical direction and slightly inclinable with respect to the outer cutter frame.
However, the aforesaid construction provides the outer cutters with a limited movable range relative to the outer cutter frame, thus presenting a problem in that the close contact between the outer cutters and skin is restricted with resultant unsatisfactory shaving feeling or inadequate user-friendliness. It has been proposed, therefore, to provide a rim which is movable relative to the main body (the rim being also referred to as an outer cutter rim, an cutter circumferential rim, a skin supporting rim or a skin protecting rim) between the outer cutters and the main body (the outer cutter frame) so as to expand the movable range and the inclinable range of the outer cutters.
JP 9-503424(T) (corresponding to WO 96/02368, U.S. Pat. No. 5,625,950 and EP 0719203) discloses a shaving apparatus which has a skin supporting rim (6) provided between an outer cutter and a main body (an outer cutter frame and a holder 2). The outer cutter is held by the rim such that it is slightly movable in a vertical direction and also slightly inclinable, and the outer periphery of the rim is pivotally supported by the outer cutter frame of the main body. More specifically, the rim enters a circular opening of the outer cutter frame, and a pair of projections provided on the outer periphery of the rim is engaged with the inner peripheral surface of the opening provided in the outer cutter frame. In other words, a pivotal supporting section is disposed between the outer periphery of the rim and the opening of the outer cutter frame.
JP 2007-151925(A) (corresponding to US 2007-124936 (A1)) discloses a shaving apparatus in which the outer periphery of a rim (a cutting member frame 18) is pivotably supported on the inner side (adjacent to the center of the outer cutter) of an upright wall (a supporting section 54) provided on a main body.
Both shaving apparatuses disclosed in the documents of the prior arts each has a pivotal supporting section provided between the rim and a fixed unit (the outer cutter frame or the upright wall) of the main body surrounding the rim, thus presenting a problem in that the width of the rim in the radial direction is limited or the outer cutter frame of the main body surrounding the rim inevitably becomes large. In particular, a small width of the rim in the radial direction causes the outer cutter to strongly abut against the skin when the outer cutter is pressed against the skin, thereby a consequent high contact pressure is applied by the outer cutter. At this time, the outer cutter slightly moves down relative to the rim, however, the movable amount thereof is limited, leading to a high pressure of contact between the outer cutter and the skin. This may give rise to a problem of easily hurting the skin.
Further, the pivotal supporting section is exposed between the outer periphery of the rim and the main body (the outer cutter frame or the upright wall), so that shaving debris easily adhere to the pivotal supporting section. This may lead to unsmooth operation of the pivotal supporting section and may prevent the rim from effecting pivotable movement, resulting in poor shaving feeling. In addition, there has been a problem in that shaving debris are not easily removed.